Re: [PATCH v5 11/17] tpm: move TPM space code out of tpm_transmit()

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Thu, Nov 08, 2018 at 10:16:54AM -0500, Stefan Berger wrote:
> On 11/8/18 9:15 AM, Jarkko Sakkinen wrote:
> > Prepare and commit TPM space before and after calling tpm_transmit()
> > instead of doing that inside tpm_transmit(). After this change we can
> > remove TPM_TRANSMIT_NESTED flag from tpm2_prepare_space() and
> > tpm2_commit_space() and replace it with TPM_TRANSMIT_UNLOCKED.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > ---
> >   drivers/char/tpm/tpm-dev-common.c | 30 ++++++++++++++++++++++++++----
> >   drivers/char/tpm/tpm-interface.c  | 29 +++--------------------------
> >   drivers/char/tpm/tpm2-space.c     | 14 +++++++-------
> >   3 files changed, 36 insertions(+), 37 deletions(-)
> > 
> > diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
> > index cbb0ee30b511..40c1cb09ebd2 100644
> > --- a/drivers/char/tpm/tpm-dev-common.c
> > +++ b/drivers/char/tpm/tpm-dev-common.c
> > @@ -30,13 +30,35 @@ static DEFINE_MUTEX(tpm_dev_wq_lock);
> >   static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
> >   				u8 *buf, size_t bufsiz)
> >   {
> > -	ssize_t ret;
> > +	struct tpm_header *header = (void *)buf;
> > +	ssize_t ret, len;
> > 
> >   	mutex_lock(&chip->tpm_mutex);
> > -	ret = tpm_transmit(chip, space, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
> > -	mutex_unlock(&chip->tpm_mutex);
> > +	ret = tpm2_prepare_space(chip, space, buf, bufsiz);
> > +	/* If the command is not implemented by the TPM, synthesize a
> > +	 * response with a TPM2_RC_COMMAND_CODE return for user-space.
> > +	 */
> > +	if (ret == -EOPNOTSUPP) {
> > +		header->length = cpu_to_be32(sizeof(*header));
> > +		header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > +		header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
> > +						  TSS2_RESMGR_TPM_RC_LAYER);
> > +		ret = sizeof(*header);
> > +	}
> > +	if (ret)
> > +		goto out_lock;
> > 
> > -	return ret;
> > +	len = tpm_transmit(chip, space, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
> > +	if (len < 0)
> > +		ret = len;
> > +
> > +	if (ret)
> > +		tpm2_flush_space(chip);
> > +	else
> > +		ret = tpm2_commit_space(chip, space, buf, &len);
> > +out_lock:
> > +	mutex_unlock(&chip->tpm_mutex);
> > +	return ret ? ret : len;
> >   }
> > 
> >   static void tpm_dev_async_work(struct work_struct *work)
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index a6ffd0960ae5..7bec03e46043 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -147,27 +147,12 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> >   		return -E2BIG;
> >   	}
> > 
> > -	rc = tpm2_prepare_space(chip, space, buf, bufsiz);
> > -	/*
> > -	 * If the command is not implemented by the TPM, synthesize a
> > -	 * response with a TPM2_RC_COMMAND_CODE return for user-space.
> > -	 */
> > -	if (rc == -EOPNOTSUPP) {
> > -		header->length = cpu_to_be32(sizeof(*header));
> > -		header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> > -		header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
> > -						  TSS2_RESMGR_TPM_RC_LAYER);
> > -		return sizeof(*header);
> > -	}
> > -	if (rc)
> > -		return rc;
> > -
> >   	rc = chip->ops->send(chip, buf, count);
> >   	if (rc < 0) {
> >   		if (rc != -EPIPE)
> >   			dev_err(&chip->dev,
> >   				"%s: tpm_send: error %d\n", __func__, rc);
> > -		goto out_space;
> > +		return rc;
> >   	}
> > 
> >   	if (chip->flags & TPM_CHIP_FLAG_IRQ)
> > @@ -182,8 +167,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> > 
> >   		if (chip->ops->req_canceled(chip, status)) {
> >   			dev_err(&chip->dev, "Operation Canceled\n");
> > -			rc = -ECANCELED;
> > -			goto out_space;
> > +			return -ECANCELED;
> >   		}
> > 
> >   		tpm_msleep(TPM_TIMEOUT_POLL);
> > @@ -192,8 +176,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> > 
> >   	chip->ops->cancel(chip);
> >   	dev_err(&chip->dev, "Operation Timed out\n");
> > -	rc = -ETIME;
> > -	goto out_space;
> > +	return -ETIME;
> > 
> >   out_recv:
> >   	len = chip->ops->recv(chip, buf, bufsiz);
> > @@ -203,12 +186,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
> >   	} else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length))
> >   		rc = -EFAULT;
> > 
> > -out_space:
> > -	if (rc)
> > -		tpm2_flush_space(chip);
> > -	else
> > -		rc = tpm2_commit_space(chip, space, buf, &len);
> > -
> >   	return rc ? rc : len;
> >   }
> > 
> > diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
> > index f35ac941c3a4..9c009db15f88 100644
> > --- a/drivers/char/tpm/tpm2-space.c
> > +++ b/drivers/char/tpm/tpm2-space.c
> > @@ -39,7 +39,7 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space)
> >   	for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
> >   		if (space->session_tbl[i])
> >   			tpm2_flush_context_cmd(chip, space->session_tbl[i],
> > -					       TPM_TRANSMIT_NESTED);
> > +					       TPM_TRANSMIT_UNLOCKED);
> >   	}
> >   }
> > 
> > @@ -84,7 +84,7 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
> >   	tpm_buf_append(&tbuf, &buf[*offset], body_size);
> > 
> >   	rc = tpm_transmit_cmd(chip, NULL, &tbuf, 4,
> > -			      TPM_TRANSMIT_NESTED, NULL);
> > +			      TPM_TRANSMIT_UNLOCKED, NULL);
> >   	if (rc < 0) {
> >   		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
> >   			 __func__, rc);
> > @@ -133,7 +133,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
> >   	tpm_buf_append_u32(&tbuf, handle);
> > 
> >   	rc = tpm_transmit_cmd(chip, NULL, &tbuf, 0,
> > -			      TPM_TRANSMIT_NESTED, NULL);
> > +			      TPM_TRANSMIT_UNLOCKED, NULL);
> >   	if (rc < 0) {
> >   		dev_warn(&chip->dev, "%s: failed with a system error %d\n",
> >   			 __func__, rc);
> > @@ -170,7 +170,7 @@ void tpm2_flush_space(struct tpm_chip *chip)
> >   	for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
> >   		if (space->context_tbl[i] && ~space->context_tbl[i])
> >   			tpm2_flush_context_cmd(chip, space->context_tbl[i],
> > -					       TPM_TRANSMIT_NESTED);
> > +					       TPM_TRANSMIT_UNLOCKED);
> > 
> >   	tpm2_flush_sessions(chip, space);
> >   }
> > @@ -267,7 +267,7 @@ static int tpm2_map_command(struct tpm_chip *chip, u32 cc, u8 *cmd)
> >   static int tpm_validate_command(struct tpm_chip *chip, struct tpm_space *space,
> >   				const u8 *cmd, size_t len)
> >   {
> > -	const struct tpm_input_header *header = (const void *)cmd;
> > +	const struct tpm_header *header = (const void *)cmd;
> 
> 
> You'll have to move this...

Thanks, I'll fix it.

/Jarkko